A: Distribution of HMW and LMW adiponectin complexes quantified by densitometry. B: western blot under non-reducing and non-denaturing SDS-PAGE conditions showing high molecular weight oligomers (HMW) migrating at approximately 340 kDa, low molecular weight hexamers (LMW) migrating at 160 kDa and trimers migrating at 67 kDa. Lanes 1–3: umbilical plasma (1, 2, and 4 ul per well) from one representative female fetus, lanes 4: molecular mass markers, lanes 4–6: umbilical plasma (1, 2 and 4 μl per well) from one representative male fetus. Data are means ± SE with n = 5 females and 4 males from the cohort of subjects described in Table 1 matched for maternal age, gestational age and ethnicity. C: Total adiponectin in umbilical plasma at delivery with n= 61 males and 60 females. *p<0.001 between males and females.